The present invention relates to a method of removing particulates suspended in steam discharged from an autoclave forming part of a solid waste treatment system following processing of solid waste. The present invention also relates to a solid waste treatment system comprising apparatus for the same.
Mechanical heat treatment (mechanical heat treatment) has for some time been proposed as a method for processing solid waste, particularly municipal solid waste. Incoming waste streams are typically screened and then sealed in an autoclave whereupon the waste is charged with steam. An autoclave-based solid waste treatment system is disclosed in International patent publication WO 03/024633 A1, which was devised by the same inventor as the present invention.
During processing, temperatures in the autoclave are typically held at around 160 degrees Celsius at 5 bar gauge for 30 to 60 minutes, with the autoclave rotating to agitate its contents. Vanes in the interior of the autoclave, in conjunction with the rotation, ensure that the waste is uniformly exposed to the steam environment.
Due to this agitation, it is typical for glass and ceramics to be lifted to a height and then fall, causing them to break. These abrasive shards, splinters and particulates become dispersed throughout the treated waste. This can cause damage to downstream plant during evacuation of the autoclave.